Shares in several Hong Kong-listed companies fell more than 70% suddenly on Thursday.

Investors and analysts are baffled as to what caused the sudden plunge.

Jiayuan, a property developer, was the worst impacted by the crash, dropping as much as 81%, and seeing more than $HKD25 billion ($3.2 billion) wiped from its market capitalization in a single afternoon.

The stock price of several Hong Kong-listed companies plunged during trading Thursday, leaving investors and analysts baffled as to what...

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By now virtually every trader has personally experienced or participated in a flash crash, whether in FX (most recently two weeks ago when numerous Yen carry pair suddenly tumbled), in stocks or in bonds. But few have observed a flash crash which sparks a domino effect of even more flash crashes.

Well, that's precisely what happened in Hong Kong overnight, when a string of local stocks plunged without warning and without any news in afternoon trading, the second perfectly unpredictable flash...

The Hang Seng Index closed down 2.8 percent, its biggest loss since Oct. 23. Cnooc Ltd. was the worst performer, suffering its largest drop in nearly three years. The Hang Seng China Enterprises Index retreated below the 10,000 level, closing at its lowest since February 2017, while the Shanghai Composite